Why can I not create a map with the following generics?
Map<Class<K extends Item>, K> classMap;
Why can I not create a map with the following generics? Map<Class<K extends Item>,
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Why can I not create a map with the following generics?
Map<Class<K extends Item>, K> classMap;
Because
Mapis already generified – your job when creating a reference is to fill in the type parameter. Unless this is inside a method parameterized withK, the compiler will have no idea whatKshould be replaced with (and if it were inside a parameterized method, you couldn’t haveK extends Itemin the body –Keither already extendsItem, or it doesn’t).New type parameters can go in the signatures of classes and methods with the implicit promise that they will be filled in later. They cannot go inside declarations.